"If Russia is the principal culprit, we can take further action against them and make it clear this kind of sponsored war is completely unacceptable."

Claiming Russian president Vladimir Putin was "egging on" the rebels, Mr Fallon added: "It is sponsored terrorism as far as people of east Ukraine are concerned. We don't know if somebody said, 'let's bring down a civil airliner, wherever it's from', - but we need to find out.

"They need to get out of east Ukraine and leave Ukraine to the Ukrainians."